Manufacture of pins, links, and the like from manganese steel.



To all whom it may concern."

UNITED ATES PATENT OFFICE.

wmrmnns. Permit, or new YORK, N. Y., assronon. 'ro ALLOY s'mnr. rename c onrm, or wrmrmemon; nmwaane conrom'rron or DELAWARE. v

muracrunn or rms, Qantas, AND LIKE Fnom MANGANESE 'srn'en 1,018,361. Ill'o JJrawing.

Be it known that I, WINFIELD S. Porrnn, a citizen of the United States, residing at. New York cit county of New York, State of New York, ave invented certain new and useful Im' rovements in the Manufacture of Pins, L' s, and the Like from Manganese Steel; and I do hereby declare the following to be a full,.clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to certain new and useful improvements in the manufacture, from manganese steel, of conveyor pins,

dredger pins, chain pins, links, bushings,v

beater arms for pulverizing mills, grate bars, or grizzly bars for separator chutes, and, ingeneral, similar shapes, requiring a high degree of resistance to abrasion or wear, and superior qualities of toughness, stiffness and tensile strength.

i In carrying out my invention, I usually heat a billet or blank of manganese steel to a temperature above 1125 C. and preferably to about 1150 C., until the metal is brought into a uniform and ductile condition throughout although, for some purposes, heating for a suitably long period at a temperature as low as 1050 C. may sufiice.

The blank is then rolled to form a bar and.

with a finishing temperature in the exterior parts at between about 800 C. and about 107 5 C. although a higher temperature and softer condition may prevail in the-center of'the bar. In the case of such conveyer pins or like shapes as may require punching for the purpose of forming small cotter pin holes or the like therein, or which require considerable ductility for the forming of the head portion of a pin, for example, the higher central temperature is desirable and in many cases necessary. When the bar is tobe converted into a beater arm or hammer for a pulverizing mill, however, a very high central temperature (2'. e., a temperature materially above 1075 C.) is undesirable, for the reason that when thus employed the entire cross section of the bar is Wearing metal, and will be of bet-ter'quality if finished at a nearly equal temperature below about 107 5 C. In the case of conveyor pins'however, having cotter pin holes a thin layer about the circumference of the cylindrical parts of the pin only is worn away Specification of Letters Patent. Application filed February 27, 1911. Serial No. 611,231.

Patented Feb. 20, 1912,

vportion of the bar corresponding. to these wearing parts of the pin need issue from the rolls at the low temperature which will secure the qualities desired. It will be understood, also that the center-temperature with which the bar leaves the finishing pass of the rolls should be correspondingly determined to accord with the particular use for which the ultimate product is intended, and

ing.

On its delivery from the finishing pass of the rolls, the bar may be placed in a suitable heater or heating furnace so as to prevent any considerable change in the average temperature'of the bar before it is subjected to the next step of the operation, namely, cutting the bar off into suitable lengths for the pin, beater arm, or the like to be produced. The heater in which the hot bar is placed, upon 1ssu1ng from the finishing pass of the rolls, should have a temperature preferably of about 950 C., or such a temperature that the. worked surface of the bar shall not become reheated by its hotter center to such a temperature as would cause the outer parts of the bar, corresponding to the wearing parts of the finished pin or other shape,.to be recrystallized and thus to lose the dense wrought condition due to the rolling. Where the shape to be produced is a conveyer pin, for instance, one end of the rolled bar is engaged by the feeding mechanism of a heavy punch press or'other machine to which the bar is rapidly fed. As the bar passes through this machine, it is out to the desired lengths,

with the ductility necessary for final formand has its endsformed by pressing, swagafter the, other from the last mentioned heater, and are inserted in thedies of a bull dozer or other suitable mechanism for com-. pleting the forming, as, for example, formmg the end of the pin, which has hitherto been left blank, into an upset head or other- Such . outer portions of the piece a er the bar has wise as may be desired. The pins are now removed from .the bull dozer and immediately uenched in water or otherwise rapidly coo led fromasubstantially equal temperature ofabout 950 0. or the finished pieces ma be held in a furnace for a short time at a out their average finishing temperature, to eliminate forging strains, before quenching.

It is important that, after the bar has once been rolled, the metal should under 0 no considerable rise of tem erature in t e issued from the finishing pass of the rolls. It is also important that at no time during the operation should any portion of the bar be permitted to cool materially below 800 0. or thereabout, except that perhaps some ortion of the surf-ace during the steps of orming the piece may momentarily be somewhat colder while the bar is 1n contact with the rolls, .cold dies, punches, etc., which form it.

When small holes are to be punched throu in thick bars, the bar is preferably caused to enterthe punching press with a center temperature considerabl; above that of the surface. This renders the punching operation easier, while preserving the results of the low temperature rolling in the surface and outer layers of metal in the bar. In the second heater, the surface temperature of the bar is raised but slightly, if at all, while the temperature of the whole piece becomes substantially equal, at about 950 0., at which temperature the surface of the bar is preferably maintained from the time'itleaves the final pass of the rolls. While I prefer to thus maintain the bar at .or about this temperature of 950 0. yet, as

hereinbefore indicated, it may have a wider ran e of temperature, but in no case should it be permitted to fall substantially below 800 C. at any time during the cutting-off or forming operations.

Instead of rolling a long bar and feeding it from the heater to the punching and cutting machine hammer or press, the billet or blank from which the bar is rolled may be smaller, so that a shorter bar will result. This, will have the advantage that the shorter bar may be more speedily cut up into the desired len he and worked into the partly formed pieces, and, consequently will lose but a slight amount of heat before the next step of the operation occurs which may be the final rapid cooling, or which may be completing the intended shape prior to such rapid cooling. When the bar produced is sufliciently short, or if the forming operations areconducted with sufficient rapidity, said operations may be completed without a drop in temperature below the required range, and consequently without the necessity of employing a heating furnace or furnaces to avoid incidental temperature losses; F" What I claim is: l l. The method of forming pins, links, and the like, from manganese steel, which consists in heating a blank of manganese steel until in a uniform and ductile condition,

then rollin the heated blankto form a bar having a ense wrought condition no the parts intended to act as wearing surfaces, cutting the bar into lengths, mechanically working the lengths into the intended shapes while preserving in the wearing parts the desirable wrought state, which those parts had at the completion of the rolling operation, and finally cooling rapidly; substantially as described.

2. The method of forming pins, links, and the like, from manganese steel, which consists in heating a blank of manganese steel until in a uniform and ductile condition, then rollin the heated blank to form a bar having a ense wrought condition in the parts intended to act as wearing surfaces, cutting the bar into lengths, mechanically working the lengths into the intended shapes while maintaining the temperature of the wearing parts within a range which will prevent any substantial loss of their dense wrought condition, and finally cool mg rapldly; substantially as described.

3. The method of forming pins, links, and the like, from manganese steel, which conslsts in heating a blank of manganese steel to a temperature higher than 1125 0.,

then rolling the heated blank to form a bar having a surface temperature in the parts intended for wear not substantially lower than 800 0. nor substantially above 1075 0., maintaining the temperature of said surfaces within said range of temperature while the bar is being cut up into lengths and formed into the pins or the like to be produced, and finally rapidly cooling the finished pieces; substantially as described.

4:. The method of forming pins, links, and the like, from manganese steel, which consists in heating a blank of manganese steel to a temperature higher than 1125 0., then rolling the heated blank to form a bar having a surface temperature in the parts intended for wear not substantially lower than 800 0. nor substantially above 1075 0., and a higher interior temperature appropriate to punching, maintaining the temperature of said wearing parts with-- in said range of temperature while the bar is being cut up into lengths and formed into the punched pins or the like to be produced, and finally rapidly cooling the finished pieces; substantially as described.

'5. The method of forming pins, links, and the like, from manganese steel, which consists in heating a blank of manganese steel to a temperature higher than 1125 0.,

then rolling the heated blank to form a bar" surfaces within said yi'ange of temperature while the bar is being cut up into lengths and formed into the pins or the like to be produced, removing forging strains by equalizing the temperature in the pieces, and finally rapidly cooling; substantially as described.

6. The method of forming pins, links, and the like, from manganese steel, which consists in heating a blank of manganese steel to a temperature higher than 1125 C.

then rolling the heated blank tov form a bar having a surface temperature in the parts intended for wear not substantially lower than 800 0. nor substantially above 1075 G. maintaining the temperature of said surfaces within said range of temperature while the bar is being cut up into lengths and formed into the pins or the like to be produced, removing forging strains by equalizing the tem erature in the ieces, for ashort tune, at a out their finis ing temperature, and finally rapidly cooling; substantially as described. a

In testimony whereof I afiix my signature, in presence of two witnesses.

WINFIELD S. POTTER.

Witnesses:

LEON W. ROSENTHAL, WILLIAM H. DAVIS. 

